Molecular Probes™ PowerLoad™ Concentrate, 100X

PowerLoad™ is an optimized formulation of nonionic, Pluronic™ surfactant polyols for the solubilization of water-insoluble dyes and other materials in physiological media. These surfactants, for instance Pluronic™ F-127, have been used to help disperse acetoxymethyl (AM) esters of fluorescent ion indicators such as fluo-4, fura-2, indo-1, fluo-3, and SBFI; they appear to be required for loading of other dyes (e.g. SBFI-AM or PBFI-AM). The use of PowerLoad™ is optional with red shifted calcium indicators and other large molecular weight AM ester dyes, and may also be useful for dispersing other lipophilic probes. The concentration of Pluronic™ surfactants in PowerLoad™ is less than 0.2%. PowerLoad™ is effective in combination with water soluble Probenecid (P36400) to aid AM ester dye-loading and retention in cells that actively extrude the de-acetylated form through anion pumps. Together, these reagents allow for maximal loading of dyes with a minimum of effort in both imaging and high throughput screening (HTS) applications. Appropriate controls should be performed to make certain that PowerLoad™ is not altering the membrane properties of the cell.